Greenhouse Effect Explanations

Two extracts from an introductory article providing “A brief history of climate science” by Ed Hawkins, a climate scientist at the University of Reading. Firstly some theory:

Climate change is often seen as a recent phenomenon, but its roots are actually far older – the effects of human activity on the global climate have been discussed for more than 150 years.

In the 1820s, the French mathematician Joseph Fourier was trying to understand the various factors that affect Earth’s temperature. But he found a problem – according to his calculations, the Earth should have been a ball of ice.

The most obvious factor, the Sun, did not seem to provide enough energy to raise the temperature of Earth above freezing. Fourier’s initial ideas, that there must be additional energy coming from the Earth’s core or from the temperature of outer space, were soon dismissed. Fourier then realised that the atmosphere, which at first seemed transparent, could be playing a crucial role.

Secondly, some real world experimental results:

Guy Stewart Callendar was a steam engineer who was fascinated by the weather. He meticulously collected temperature records from around the world, examined the carbon dioxide measurements and studied the work of Arrhenius and others. In his spare time, and without the aid of a computer, he performed the tedious calculations required to measure the temperature of the planet. These efforts produced the first evidence that Earth’s surface was warming.

A demonstration of carbon dioxide absorption of infrared radiation by Iain Stewart, Professor of Geoscience Communication at the University of Plymouth: